Tundra nulorns are most active in the winter, when the snow starts to fall and the air grows cold. At this time they are busy choosing mates, a process that can take many weeks. Their bellows can be heard all the way from the castle, a deep sound that attracts females. Male nulorns strive to capture the attention of them, and engage in fights to do so. Although they are large beasts, with tremendous antlers, it is rare for them to injure one another. As soon as one has asserted his dominance, the fight ends and the victor prances off. It is the females who are more intelligent, and take on the important task of caring for hatchlings. This is an activity easier said then done, for nulorn young do not tire readily. As they age, nulorns focus their time on finding food, rather than playing. These companions eat all manner of vegetation, and much of the energy is focused on males growing antlers. While growing, these antlers are covered in a soft fuzz, which disappears over time. As winter approaches, male nulorns lose their antlers, so that the energy might be used for other means. They will regrow them in the spring. From time to time, people find their discarded antlers. After some experimentation, a magi discovered that these antlers possess a strange power. Crushed and added to potions, this powder allows anyone to navigate the Borean plains with ease. This knowledge fades after a few short hours. There is one other mystery that has yet to be understood; the tales that are still told by those who live near the northern parts of the world. These villagers say they sometimes see nulorns with tiny beings riding on their backs, beings that look much like small humans. No magi has ever been able to verify this.

Although these creatures prefer the northern parts of the world, they are sometimes seen around the castle during the winter storms. Tundra nulorns are taken out of the Borean plains by blizzards as they tend to follow in their wake. On these occasions, most magi keep their distance from the creatures. Although nulorns are peaceful companions, they are wary of humans, and will quickly disappear back into the plains if bothered. Young nulorns are less cautious, and charge into the water and snow banks at once, eager to swim and play. These companions are excellent swimmers, and can cross lakes if they so desire. If a magi has a very close bond with their nurlorn companion, the nulorn may even allow them to ride upon their backs. This is a speedy form of travel, both on land and water, as nulorns are very powerful creatures. They know almost every tree that grows in the woods, and can travel at great speed. Even deep snows do not stop them, as their wide hooves act as snowshoes. It is during the cold seasons that these companions focus all of their attention on their survival. The only food available are the few leaves that cling to the trees, and nulorns will even eat bark. Very few creatures dare to attack them, but it is in the depths of winter that they are most vulnerable. Even then, only a large pack of wolves stand any chance at bringing down a nulorn.